This laboratory is interested in the relationship among protein sequence, structure and the mechanisms of protein folding and enzymic reactions. (i) Secondary Structure of Amyloid Proteins. g-factor analysis of the CD spectra of amyloid proteins and polypeptides indicate the presence of two types of structure. Amyloid forms of ovalbumin, apomyoglobin, transthyretin and Ure2p contain 35-55% of beta sheet, whose CD spectrum is like that found in most globular proteins. The more intense spectra of beta-2-microglobulin, insulin, Abeta(1-40) peptide and various homopolypetides, in amyloid films are consistent with the presence of 50-80% of beta helix like structure. The latter result is compatible with a protofibril which contains a structural unit of approximately 45 residues in a beta helix like structure. (iii) Effect of molecular crowding and confinement on protein satbility (with YiSheng Ni and Allen Minton, NIDDK). Studies on the effect of high concentrations of dextran on the heat and cold denaturation of globular proteins.